Method of recovering fuel from residues



G. ULLRICH ET AL METHOD OF RECOVERING FUEL FROM RESIDUES Filed Sept. 1920 name ch21, rear.

F F i Q GEORG ULLBICH, FRANZ GRUESSNER, AND HANS IJYCK, OF MAGDEBURG, GERMAlNY, ASSIGINORS TO FRIED. KRUPP AK'I'IENGESELLSCHAFT GR'USONWERK, OF MAGDE- BURG-BUCU, GfiRY, A GERMAN CORPORATION.

METHOD OF RECOVERING FUEL FROM RESIDUES.

Application filed September To all whom it may concern: I

Be it known that we, Gnone ULLRICH,

FRANZ GRUESSNER, and Hans DYCK, citizens of the German Republic, residing at Magdeburg, Germany, have invented certain new and useful Improvements in Methods of Recovering Fuel from Residues, of which the following is a specification; l or invention refers to the treatment of fuel residues resulting in working furnaces, boilers and the like, and its particular object is to recover from such residues the coke and coal still present therein in a more eflicient and economical manner than has heretofore been possible.

As is well known the burnt residues from boilers, furnaces, etc.,- still contain a considerable percentage of coke and incompletel burnt coal. In order to recover these value is constituents, a wet concentrating process carried out by means of jigging machines has hitherto The burnt residues (ashes and slag} were first sifted out and worked up on igging machines and by this means the slag sepa rated from the coke and the coal according to their specific gravity. After the floating slag has been separated out from the.

coke product and the coal which has not yet been burned has been separated from the slag product by hand labor the products are passed over dehydrating sieves, in order to get rid of the water. The dirty water is run into two or three part settling tanks and subjected to a purifying process to enable it to be used over again.

The process which forms the subject matter of this invention not only requires less expense for plant and working but it insures above all things the recovery Without any residue of the fuels contained in the burnt residues, no, matter whether these are present in the form of coke or coal which has not yet been burned.

The invention is based on the idea, that the greatest part by far of the fuel residues which are no longer combustible, possess magnetic properties, which are explained by the fact that the fuel contains iron compounds to a small extent (e. g. pyrites and the like) which are converted in the fire into protoxide or sesquioxide or peroxide of iron and appear in the ashes and slag. as silicates by fusion with SiO,,. These slags been generally used.

2, 1920. Serial No. 407,749.

containing this small amount of iron are attracted and firmly retained in highly concentrated magnetic fields, while the unburnt coal and the coke remain unacted on by the magnetic fields. It is thus possible by passing the ashes through a highly concentrated magnetic field to recover the coal as a non-magnetic product and separate therefrom the constituents which contain 1t ihtlediron and are retained in the magnetic Our invention therefore substantially consists in subjecting fuel residues to the action of highly concentrated magnetic fields, such as by causing them to pass through such fields, thereby separating the fuel still contained in such residues from the incombustible slag. 1

Apart from the great reduction of the cost of the plant required and the working in general the new process has the following advantages The unburnt coal with the coke. be treated and easily recovered.

The new process permits of the recovery of the coke and unburnt coal in an easy and cheap Way from all ash and slag wastes from allv industrial works, railways, shipping and even from house refuse.

s the magnetic separation can be carried out in the dry way, the apparatus required for carrying out the new process consists only, in addition to a disintegrating apparatus which may perhaps be necessary, of the magnetic separator.

Notwithstanding the low amount of iron in the ash it is possible by the aid of specially powerfully concentrated magneticfields to'separate all slags which contain iron from the non-magnetic fuels.

In the case of slag in large pieces it may happen that in the slags containing iron, which in the magnetic as magnetic material, there are still contained fuel, coke and particles of coke, which are either enclosed in the pieces of slag or are fused thereto. In order to recover this fuel also, the slag which has already been separated as magnetic material is ground and the ground material thus obtained again is recovered together the fuel contained therein netic field. ythis means the fuel previ- Even the finest material can separation pass away ously enclosed in the slag is obtained in a meally' form as a non-magnetic product, while the slag meal asses away as a magnetic product. In or er to make it utilizable for combustion the fuel may then be briquetted together with fine fuel obtained in the first process of about 8 mm. size of.

separation the strength and consequently the.

value of the building stones thus obtained are materially increased.

In the drawings affixed to this specification and forming part thereof the novel method is illustrated diagrammatically,

gig. 1 being a diagram illustrating one, an

Fig. 2 a diagram illustrating another modification.

Referring to the drawings, a (Fig. 1) is a plate guiding the fuel residues onto a rotary magnetic separator 12 which attracts the magnetic particles and carries them out of reach of the magnetic field to' discharge them into a container .0, while the non-magnetic carbon or coke particles are thrown ofl at once to be collected in the container 01.

The modification disclosed in Fig. 2 is distinguished from the one described above by the magnetic particles which had been attracted by the separator drum, falling i onto a trough or chute e conducting them between a pair of cylinders f or the like where they are ground to meal. The finely powdered material then drops onto an inclined plate leading to another magnetic separator acting after the manner of the first one and causing the non-magnetic particles to collect in the container is, which had already received the non-magnetic particles dropping ofi the first separator drum 6, while the finely ground magnetic material is collected in the container 71.

Although in the drawings the rotar type of separator is shown, we wish it to e understood that we may as well employ any other type of separating device, preferably one having the most powerful magnetic field available.

We claim:

1. The method of separating the ashes from the unconsumed carbon constituent of the combustion residues of ferriferous fuels consisting in subjecting the residues to the action of a highly concentrated magnetic eld.

2. The method of separating the ashes from the unconsumed carbon constituent of the combustion residues of coal and coke consisting in subjecting the residues to the glcgipn of a highly concentrated magnetic I 3. The method of separating the ashes from the unconsumed carbon constituent of the combustion residues of coal and coke consisting in passing the residues, through a highl concentrated magnetic field.

4. e method of treating the combustion residues of coal and coke consisting in magnetically separating the ashes from the unconsume carbon constituent of the residues, pulverizing said ashes and subjecting them to the action of'a highly concentrated magnetic field.

In testimony whereof we afiix our signatures.

GEORG ULLRICH. FRANZ GRUESSNER. HANS DYCK. 

